Inhibition of nuclear factor-kappa B activation attenuates hydrogen peroxide-induced cytotoxicity in human lens epithelial cells

Aims: Hydrogen peroxide (H2O2) is the major oxidant involved in cataract formation. Lens epithelial cells have been suggested to be the first site of oxidative damage. The authors investigated the relationship between H2O2-induced cytotoxicity and activation of nuclear factor kappa B (NF-kappa B) in human lens epithelial (HLE) cells. Methods: HLE B-3 cells were stimulated by various concentrations of H2O2 in the presence or absence of pyrrolidine dithiocarbamate (PDTC), a potent inhibitor of NF-kappa B. H2O2-induced cytotoxicity was measured by lactate dehydrogenase cytotoxicity assay. Translocation of NF-kappa B was examined by Western blot and immunocytochemistry using anti-p65 antibody. Results: H2O2-induced cytotoxicity increased in a concentration-dependent manner. PDTC treatment significantly suppressed the cytotoxicity induced by H2O2. After stimulated with H2O2, NF-kappa B was found translocated from cytoplasm into the nuclei. PDTC treatment also inhibited the translocation of NF-kB. Conclusions: NF-kappa B signal pathway may be important in the development of H2O2-induced damage in HLE cells that is involved in cataractogenesis.